Active Scripting (formerly known as ActiveX Scripting) is the technology used in Windows to implement component-based scripting support. It is based on COM (more precisely, OLE Automation) and allows installation of additional scripting engines in the form of COM modules.
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The Active Scripting technologies were first released in 1996, with the release of the Microsoft Internet Explorer 3.0 (August 1996) and Internet Information Services 3.0 products (December 1996).
Usual applications of Active Scripting include Active Server Pages (ASP) server scripts, Internet Explorer, and Windows Script Host (WSH) scripts automating routine tasks, including use for login scripts, Registry manipulation, and the like. Other administrative uses include Windows Management Instrumentation and Active Directory Service Interfaces. Active Scripting can also be used for general-purpose scripting, such as database programming, text-processing, rapid prototyping, and application macro/scripting programming; some applications use Active Scripting as the main automation method, others do not have a macro facility but the components are available for use via the API; or one may opt to add a language and/or tool not available by default, like programming Microsoft Excel in Perl or REXX rather than Visual Basic for Applications (VBA) or transferring data from a terminal emulator to word processor by way of a spreadsheet when they have dissimilar macro tools or none at all.
For many of the above uses, Active Scripting is an addition to Windows which could be said to be similar to the functionality of Unix shell scripts, as well as an incrementation upon batch files (command.com), Windows NT style shell scripts (cmd.exe) and can even be said to be, by way of VBScript, the replacement for QBasic – which was last available on the supplementary disc for Windows 95. The majority of the languages used for Active Scripting mentioned below are therefore glue languages and Perl is the most commonly-used third-party script engine.
The interfaces to Active Scripting engines are public, so any developer can create his own applications that are programmable in Active Scripting languages as well as engines for additional languages.
VBScript and JScript engines are included with the default installation of Windows versions after Windows 95, and are an optional install with CE. According to Microsoft and third-party documentation, Visual Basic for Applications (VBA) is a third default scripting engine and is part of the Windows installation and therefore present even if there is not an installation of Microsoft Office, WordPerfect Office, or other software packages which are VBA-programmable. Active Scripting engines for other languages are also available; many are free, some are proprietary (commercial), and at least one shareware engine (a Tcl engine in the beta stage of development) is extant. For example, one can add support for Perl and Python scripting to Windows by installing the ActiveState Active Scripting engines which are included in the ActivePerl and ActivePython distributions. The standard PHP installation for Windows includes an engine known as ActivePHP and PHPScript in various versions. Scripting engines implementing other variants of Basic, Haskell, PHP, REXX (multiple versions), Delphi, XSLT, Tcl, Ruby and other languages are also available.
In Windows, CScript.exe at the command line and WScript.exe running in the GUI are the main means of implementation of installed Active Script languages. Clicking on an icon or running from the command line, a script, the Run dialogue, &c. will by default run a plain text file containing the code. Windows Script Files (.wsf) are an XML file which can contain more than one script in more than one language in addition to other elements, and are executed by the Windows Script Host.
The third-party shell Take Command can, as of version 10, be configured for direct interoperability with the script host and its installed engines.
The script host, related components, and engines are able to be integrated into and called from Windows applications just like any other component.
Active Scripting is now deprecated in favor of .NET[1], with some continuing use of run-time interpretation of JScript with JScript .NET and VBScript within ASP.NET. No new versions of the active scripting engines will be developed and they are now being supported by Microsoft's Sustaining Engineering Team, who are responsible for bug fixes and security enhancements. However version 5.6 of the scripting engines will continue to be shipped with future releases of Microsoft Windows and IIS[2]. Microsoft has also introduced Windows PowerShell which can expose applications via PowerShell cmdlets and/or PowerShell providers.
Originally, the .NET Framework had a scripting technology of its own and a separate scripting IDE called Visual Studio for Applications (VSA)[3][4], and the interfaces to the technology were also available via Active Scripting, allowing even .NET-unaware applications to be scripted using .NET languages. VSA was also meant to replace Visual Basic for Applications[5].
However, that entire technology was deprecated in version 2.0 of the .NET Framework,[5] leaving no clear upgrade path for applications desiring Active Scripting support (although "scripts" can be created in C#, VBScript, Visual Basic .NET, and other .NET languages, which can be compiled and executed at run-time via libraries installed as part of the standard .NET runtime).
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